Insomnia Causes: What You Should Know

Insomnia is more common than you might think. In fact, nearly 70 million Americans¹ have a sleep disorder, with 30% experiencing short-term insomnia and 10% long-term insomnia. However, many people don't realize they are experiencing insomnia.

According to The American Academy of Sleep Medicine and the Sleep Research Society, people between the ages of 16-60 years old should sleep at least seven hours² for optimal health.

If left untreated, insomnia can have long-term effects on the body and essentially reduce your quality of life.

Have you considered clinical trials for Insomnia?

We make it easy for you to participate in a clinical trial for Insomnia, and get access to the latest treatments not yet widely available - and be a part of finding a cure.

Understanding insomnia

Everyone has trouble sleeping occasionally, but insomnia is a common sleep disorder that makes it difficult to fall asleep, stay asleep, or causes a person to wake up too early and not get back to sleep.

This disorder can be short-term but can also be chronic. It's important to note that insomnia may come and go throughout life.

A person with acute insomnia may experience the disorder from one night to a few weeks. Your insomnia is chronic if it happens at least three nights a week for three months or more.

Insomnia can be classified as primary and secondary.

  • Primary insomnia is when the sleep disorder is not linked to any other health issue.

  • Secondary insomnia is when individuals have sleep problems due to an underlying health condition such as asthma, depression, arthritis, or pain.

Primary and secondary insomnia are further broken down into categories that describe various characteristics of insomnia.

  • Sleep-onset insomnia: A person has trouble falling asleep.

  • Sleep-maintenance insomnia: A person has trouble staying asleep through the night or wakes up too early. 

  • Mixed insomnia: With this form of insomnia, a person will have trouble both falling asleep and staying asleep through the night. 

  • Paradoxical insomnia: A person with paradoxical insomnia underestimates the time they are asleep. As a result, it feels like they're sleeping a lot less than they really do. 

What causes insomnia?

There are a variety of factors that can lead to insomnia. The cause of insomnia will depend on whether it is primary or secondary. Here are some factors to consider.

Causes of primary insomnia

Primary insomnia is not linked to an underlying health condition. Causes of this type of insomnia include:

  • Stress: This is a feeling of being overwhelmed or unable to cope with mental or emotional pressure. Stress can be related to major life events, such as job loss or job change, the death of a loved one, divorce, or moving. 

  • Sensory: Your surrounding environment, including noise, light, and temperature, can cause insomnia. 

  • A shift in your sleep schedule: Experiencing changes in your sleep schedule such as jet lag, a new work shift, or habits that you've picked up due to other health problems can lead to insomnia. 

  • Genes: Research shows that insomnia tends to run in families³.

Causes of secondary insomnia

Secondary insomnia is linked to an underlying health condition. Causes of this type of insomnia include:

  • Mental health: Having mental health issues such as anxiety and depression can cause insomnia. In fact, about 50% of insomnia⁴ cases are linked to depression, anxiety, or psychological stress. 

  • Medications: Certain medications such as colds, allergies, asthma, and high blood pressure can disrupt sleep patterns. 

  • Hypothyroidism: This is a condition in which your thyroid gland doesn't produce enough of certain crucial hormones. For individuals with hypothyroidism, falling asleep or staying asleep may be difficult. 

  • Pregnancy: It's not uncommon for pregnant women to develop insomnia, especially during their first trimester. This is due to symptoms associated with pregnancy, such as an increased need to urinate, nausea, vomiting, and back pain. 

  • Pain: Pain or discomfort at night can make falling asleep difficult. 

What are the risk factors for developing insomnia?

There are various risk factors associated with insomnia. However, it's important to note that a person can develop insomnia with or without risk factors. But the more risk factors you have, the more likely you are to develop insomnia. Here are some factors to know. 

Advanced age

Research shows that individuals 60-65 years or older⁵ are more likely to have insomnia than younger people. This may be due to the fact that older adults are less likely to sleep due to bodily changes related to aging.

Chronic diseases

Certain chronic diseases and associated pain may increase your risk of developing insomnia. Some chronic diseases include:


Side effects of certain medications can increase a person's risk of developing sleeping problems. These medications may include:


Studies show that the rate of insomnia is higher in women compared to men⁶. This may be a result of various hormonal changes that women experience.

Lifestyle behaviors

Certain habits and activities can increase your likelihood of developing insomnia, such as smoking or using tobacco products, exercising close to bedtime, following an irregular morning and nighttime schedule, and drinking alcoholic beverages.

Psychological factors

Individuals who experience intense and long-term stress have one of the most significant risks of developing insomnia.

The lowdown

Sometimes we have trouble falling asleep. But for some people, sleep disruption is due to insomnia. Insomnia can be acute, lasting only a short period of time. But it can also be chronic and come and go throughout life.

With that said, there are a variety of factors that can trigger insomnia. These factors will depend on whether your insomnia is primary or secondary.

It's important to note that there are certain risk factors for developing insomnia, such as age, gender, psychological factors, chronic diseases, and medications.

  1. Insomnia Facts and Statistics | The Recovery Village

  2. 1 in 3 adults don’t get enough sleep | CDC

  3. Familial Aggregation of Insomnia | Oxford Academic

  4. Sleep Disorders | National Alliance on Mental Illness

  5. Insomnia in the Elderly: A Review (2018)

  6. Insomnia | OASH: Office on Women's Health

Have you considered clinical trials for Insomnia?

We make it easy for you to participate in a clinical trial for Insomnia, and get access to the latest treatments not yet widely available - and be a part of finding a cure.

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